| 时间 | 平均 | 最高 | 最低 |
|---|---|---|---|
| 2025 | 1.3 | 1.46 | 1.18 |
| 2024 | 1.03 | 1.38 | 0.79 |
| 2023 | 1.22 | 1.5 | 1 |
| 2022 | 1.48 | 1.8 | 1.15 |
| 2021 | 1.15 | 1.4 | 1 |
| 2020 | 1.18 | 1.6 | 1 |
| 2019 | 1.5 | 1.87 | 1.3 |
| 2018 | 1.87 | 2.2 | 1.36 |
| 2017 | 1.65 | 2.15 | 1.22 |
| 2016 | 1.97 | 2.51 | 1.53 |
| 2015 | 2.15 | 4.33 | 1.16 |
| 2014 | 0.63 | 1.36 | 0.44 |
| 2013 | 0.61 | 0.85 | 0.47 |
| 2012 | 0.58 | 0.82 | 0.39 |
| 2011 | 0.68 | 0.92 | 0.42 |
| 2010 | 0.67 | 0.83 | 0.5 |
| 2009 | 0.45 | 0.8 | 0.17 |
| 2008 | 0.35 | 0.8 | 0.13 |
| 2007 | 0.69 | 1.06 | 0.33 |
| 2006 | 0.21 | 0.39 | 0.16 |
| 2005 | 0.2 | 0.3 | 0.14 |
| 2004 | 0.74 | 1.91 | 0.25 |